Stomach Issues Weight Loss. Tests done?

Since 2 3 months hvng stmch issues like semi digested motions, cramp, indigestion. But on 16th june had cramp frequent motions with mucus since that day i am having cramp, frequent motions, cramp, mild fever, headache, red eyes. Done ultrasound which is normal, and have grade 1 fatty liver. Since 16th june done infection course three times consulted 2 senior gastro one has done infection course twice and after that written many test like ctscan, clonoscopy, endoscopy,biopsy, anti tgt, while other Senior gastro saying its IBS and no need for test. Now my concern is why frequent infections, headache, extreme weakness and i lost 6 kg weight during this however in last three weeks weight is normal it is around 70kg some time it comes 70.5kg some time 69.4 recently it was 70kg. I am confused what to do? Whether should i get these tests done? Or should i accept it IBS & Continue this treatment. I am worried about my health pl guide